hey everyone . i have a 2001 sunfire with the 2200 4 speed auto .i recently put a j tuners turbokit and intercooler kit on. i have some rc 310cc injectors with a cartech 2025 fmu . now just recently the car has been acting up . when i start it , it studders and it lets out a lot of black smoke out the exhaust. and when i go to get on it it studders very bad and won't go anywhere at all . today i floored it and it sounded like it was bogging down and it was pouring out black smoke . i have a narrowband af gauge . i know thats does nothin but atleast i can see alittle before i get my wideband . when it starts acting up it goes very lean. but at the same time it gets to much fuel ..... like i said when i floor it to go it might go 1 mph ... seriously. then after about 20 seconds of the pedal to the metal it will start to studder real fast , then all of a sudden it goes away and my car hauls ass. ... i was told a few reasons why this is happening . personally i think its because i have to big of injectors on the car and the extra fuel is foulling out the o2 sensor . what yall think . ? any opinions will greatly be appreciated. i am getting the hptuners prgram and i am upgradeing my ignition syste,m to msd blaster coils, magnicore spark plug wires, and ngk tr6 ix spark plugs. i also bought a new o2 sensore i will replace when i change out the other things.
from what i understand from recent experience and research is that if the spark is getting blown out by too much fuel, you will see the black smoke but the O2 sensor (both wide and narrow band) will likely read extremely lean as there will be a ton of unburnt air in the exhast. there are 2 things i would try in your situation : decrease the Acell enrichment amount and/or increase spark power. one or the other may fix the problem or it may need both. i personally needed both.
Sounds to me your FMU is set wrong. Too much fuel. It you are not even getting 1mph you are not building boost yet so it would not be blowing spark out. What are you plugs gapped at?
I DON'T KNOW THERE STOCK PLUGS ... BUT I JUST BOUGHT SOME NGK TR6'S ... WHAT SHOULD I GAP THEM AT? 35? o sorry botu the caps i didn't realize.